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GEOMETRY PRETEST REVIEW
Reviewing skills needed to succeed in Geometry.
Day 1
REDUCING FRACTIONS
12 3  4 4


15 3  5 5
Look for common factors, and cancel them out to 1.
SIMPLIFYING EXPRESSIONS
What does it mean to simplify?
Look out for the distributive property
Combine like terms
Example:
Simplify.
2𝑥 − 3 4 + 8𝑥
5 STEPS FOR SUCCESSFUL EQUATION SOLVING
Step 1: Perform any distribution; look for ( ).
Step 2: Combine like terms on each side of =
sign.
Step 3: Add or subtract variable terms to get
all variables on the same side of the = sign.
Step 4: Isolate the variable term by
subtracting (-) or adding (+) the constant
(number with no variable) from each side of
the equation.
Step 5: Isolate the variable by dividing both
sides of the equation by the coefficient of the
variable term.
Example:
Solve.
2𝑥 − 4 + 10𝑥 = 12
SOLVING PROPORTIONS
oAn equation that shows two
16
4
equal ratios, such as =
12
3
oUse the Cross Product Property
to solve!!
a c

b d
ad = bc
Example:
Solve.
3
2
=
𝑥−5 3
THE COORDINATE PLANE
Has 4 quadrants
The origin is at (0,0)
Coordinates are 𝑥, 𝑦 .
𝑥 is horizontal coordinate
𝑦 is vertical coordinate
SLOPE
Slope measures how steep a line is.
 There are 4 kinds of slope.
To find the slope between 2 points
on a line:
y2  y1
m
x2  x1
SLOPE
Parallel lines have the same slope.
Perpendicular lines have opposite, reciprocal slopes.
Example: Find the slope of the line shown below:
FORMS OF EQUATIONS OF A LINE
We will use this
form most
often in this
course.
WRITING THE EQUATION OF A LINE
Need a point on the line and the
slope of the line
If given 2 points, find the slope first,
then use either point
Use algebra to move back and forth
between forms of a line
Example:
Write the equation in slope
intercept form of the line that
passes through point (-2, 1) and has
a slope of 3.
GRAPHING A LINE USING INTERCEPTS
Can graph using intercepts or in slope-intercept form.
A x-intercept is where a line
crosses the x-axis. To find it
algebraically you plug in 0 for y.
A y-intercept is where a line
crosses the y-axis. To find it
algebraically you plug in 0 for x.
GRAPHING A LINE USING 𝑦 = 𝑚𝑥 + 𝑏
To graph in slope-intercept (𝑦 = 𝑚𝑥 + 𝑏 ):
 Graph the y-intercept
 Use slope to graph other points
Example:
Graph the equation: 𝑦 = 2𝑥 + 1
y intercept: _____
Slope: ______